[TIP] instantiate class and use in all tests

[James]

Can I instantiate a class (DoStuff) and make it available to all my tests?
I get  an error with the following code:
==================================== ERRORS 
====================================
________________________ ERROR collecting testscript.py 
________________________
testscript.py:14: in <module>
     @pytest.mark.incremental
testscript.py:16: in TestAclass
     ds=DoStuff(a,b)
E   NameError: name 'a' is not defined

Even if I can't pass in a and b, can I still make a ds and use it in my 
tests?


# conftest.py
import pytest

@pytest.fixture(scope='module')
def need_a(request):
     value = request.config.getoption("A")
     if not value:
         pytest.skip('test needs -A option to run')
     return value

@pytest.fixture(scope='module')
def a(request):
     a = pytest.config.getoption("A")
     return a

@pytest.fixture(scope='module')
def b(request):
     b = pytest.config.getoption("B")
     return b

def pytest_addoption(parser):
     parser.addoption("--A", action="store", default=None, help="a option")
     parser.addoption("--B", action="store", default=None, help="b option")

import pytest

# testscript.py

class DoStuff():
     def __init__(a,b):
         self.a=a
         self.b=b

     def log(self,msg):
         # do logging stuff
         pass

@pytest.mark.incremental
class TestAclass():
     ds=DoStuff(a,b)

     def test_1(self,request):
         print 'inside {0}-{1} 
step'.format(self.__class__.__name__,request.function.__name__)
         print 'a={0}, b={1}'.format(ds.a,ds.b)
         ds.log("we are here")
         pass


     def test_2(self,request):
         print 'inside {0}-{1} 
step'.format(self.__class__.__name__,request.function.__name__)
         print 'a={0}, b={1}'.format(ds.a,ds.b)
         ds.log("we are here2")
         pass